Sunday’s second annual “Wax & Wine” is a fundraiser for the nonprofit San Dieguito River Valley Conservancy. Besides indulging in wine and food, guests will have an opportunity to make their own beeswax candles with expert guidance.

That’s because the 1 to 4 p.m. party is at the Knorr Candle Shop at 14906 Via de la Valle in Del Mar.

The price of admission, $50 for conservancy members and $75 for non-members, will cover gourmet fare, wines paired by guest chefs and candles — plus provide a financial boost to the river park.

Established in 1989, the park follows the San Dieguito River from Julian’s Volcan Mountain to the seashore in Del Mar. That’s 55 miles as the crow flies and 70 miles as the human hikes.

The goal is to have a network of trails around and beside the river. The 70-mile “Coast to Crest Trail,” paralleling the river’s meandering course, is now about 45 miles complete.

Filling in the gaps is a costly undertaking, especially in coastal areas. The quarter-mile River Path Del Mar, which opened in May, was a $450,000 endeavor.

The conservancy is a major supporter of the park but not the only one. There’s another nonprofit, the Friends of the San Dieguito River Valley, and the San Dieguito River Park Joint Powers Authority, authorized by its member agencies — San Diego County, plus the cities of Del Mar, Escondido, Poway, San Diego and Solana Beach — to create the park.

Help also comes from businesses, foundations and private property owners who live along the river.

Still, this is a big job for a small group. The conservancy has 3,500 sustaining members but only two staffers: Boaz and conservation manager Jessica Norton.